Hi guys. So I unplugged my PC for about a week (outstation). When I come back home, it won't turn on, the power led was on and fans were spinning for half a sec then it just shuts off.

I opened the case. Basically reconnecting everything, and it started again normally. I thought it was just the mobo power cable connection. I even game on it for a bit this morning. Suddenly, just after finished gaming (game closed already), the pc shuts off by itself, and tries to start back up and fails again in a loop.

Any ideas?

Not currently. Planning to borrow a friend's but his is only a 250w. Is it enough for a i5-3470 and a 7870?

Yeah, I just want to isolate the issue to the psu.

Hi sifus. An update here. I tested my pc with a friend's psu. An aerocool 550w 80+ bronze and it still does not work. Does this mean the problem is not psu? Any ideas on the next step?

Reset cmos even if I did have never messed with the bios?
Everything else was plugged. I only meant the power to the psu was off.

This post has been edited by Ronin_Amin: Nov 30 2015, 06:52 PM

Yeah the surge damage is one of my concerns. But wont the psu be fried first?

Yup. Lan as internet connection. So just to confirm, since I used my friend's PSU and it still doesn't start, my PSU is fine right?

Yeah the psu fan is still running. I just used the normal method to turn it on.

This post has been edited by Ronin_Amin: Dec 1 2015, 02:13 PM

Is it considered a restart loop it it just turns on the fan for a sec and then the power led lights up and everything turns back off and the whole thing starts again? Monitor does not even turn on.

I have already reopened the system and reconnected all the cables. Nothing unusual was found.

cmos died due to lightning? Where to buy cmos? All mobo same cmos?

So how properly confirm it is the motherboard?

Since I think the PSU is ok (because used friend PSU on pc and still same problem), should I also test my PSU to power up a friends pc? If the PSU is faulty, would this cause problem to their pc?

Also since people suggest it might be a corrupted hard disk, I was thinking of putting my ssd in a friends pc and see if it can boot.

I guess the first step is to try if it can boot with only the ssd, cpu, mobo and ram?

Would secondary hard drives being corrupted cause this problem?

Sorry for so many unstructured questions, really worried about this.

Owh, I got a 550w PSU from a friend. So that's ok.

Well there is the fans spinning for a bit and power led on but both stop and restart again. I guess that means it's probably not the ssd? I will also try using the ssd in a friends PC this weekend to make sure the ssd is not the cause.


Any idea where to buy cmos battery? Yeah I am planning to test the ram and the ram slots. Only have 1 stick though.

Any testing would have to wait till this weekend as I am once again away from home. I unplugged everything from wall this time though.
I really was planning to keep the CPU, mobo, and ram for a few generations as the CPU improvements are great for gaming. Does gigabyte motherboard have 3 year warranty? Otherwise might have to look for a mobo for i5-3470.

Thanks for the help so far. Will keep this updated.

Yeah, I only know that a lightning struck my house causing a blackout. Not entirely sure if it surged my pc or not (hopefully not). I guess the mobo (possibly) just died randomly?

Sorry by that I mean switch off. Everything was still plugged to the wall and even lan cable was plugged.

Update:
After I come back to my house and plugged all the power cables, suddenly my pc turns on.
Things I changed
1. I didn't cable manage, just plug it all the power cables so I can just test the pc for a while.
2. I didn't use an extension cable for the power cable to the 4 pin cpu socket. I used this before to get a neater cable managment.

I am somewhat sceptical that the problem is solved since the last time it turned on, after about 12 hours the problem start again.

So sifus any idea? Do you think it was the cpu extension cable?

I have been running memtest all night, I think 9 passes currently. I am thinking of doing a cpu stress test, gpu stress test, and psu stress test afterwards. Just to eliminate other possibilities.

So does this mean my mobo is fine?

Alright. That's good. So if it was the loose psu connectors can I just tape or should I send back for RMA?

So I think I have the cause. It was the 4-pin cable extension. It seem to have burned at the end. Everything is running fine now but should I be worried about what was causing the burn in the first place?

4-pin cable

I also don't know how to post picture on these forums lol

This post has been edited by Ronin_Amin: Dec 6 2015, 07:54 PM

The 4-pin cable from the psu couldn't reach the cpu pin on the mobo if I were to wired it behind the case. Essentially, it was for better looking cable management. I only overclock my GPU and I didn't even mess with the voltage of that.